This invention relates to a gas spring having a lead screw drive within a cylinder, and wherein the gas spring provides both a driven and manual mode.
Gas springs are utilized to cushion and control movement between a movable member and a fixed frame. One major application of gas springs is in connecting a vehicle closure to the vehicle frame. As an example, rear lift gates, hatchbacks, etc. typically include a gas spring at each lateral side that drive and cushion movement of the closure between open and closed positions.
One additional feature sometimes used in combination with a gas spring is a drive mechanism for driving the closure, such as when an operator requests the closure be moved between the open and closed positions. The drive mechanism typically includes a motor and linkage separate from the gas spring. The gas spring still assists movement of the closure, and will hold the closure at the open position. However, the motor drives the linkage to move the closure between the open and closed positions, and provides a good deal of the drive force.